From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test results for an A.T. Speedometer removed from chassis 12-EX for laboratory testing.
| Identifier | ExFiles\Box 50\4\ Scan143 | |
| Date | 23th August 1927 | |
| X4308 EFC {E. Fowler Clarke - Electrical Engineer} /T23.8.27. A.T. SPEEDOMETER X.4308. Standard A.T. speedometer No. A246. 745. 15/52. belonging to chassis 12-EX has been removed for test in the laboratory previous to a long run. The result of the test is as follows :- At a speed of 599 r.p.m. and a temperature of 18.0°C the m.p.h. indicated were 47.6. After the instrument has run for a considerable time, on the car, it is to be re-tested to see if any loss of magnetism of the permanent magnet has occurred. EFC. {E. Fowler Clarke - Electrical Engineer} A.246. | ||